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Nov. 12, 1929. H, |DE 1,735,435

VAR IABLE CONDENS ER Filed Jan. 21. 1926 29 arry/Z 0 5.

' operating poses. These condensers may, as shown in thepresentemb'odiment of the inventlon, be

Patented Nov. 12, 1929 UN T D STATES ATENT Fries HARRY H. nn, OF LAGRANGE, ILLINOIS, AssI GNOR T KE LLOG SWITCVHBOAIRD & SUPPLY COMPANY, OFCHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS VARIABLE CONDENSER 1Application filed January 21, 1926. SerialNO. 82,638. I

This invention'relates'toimprovements in variable condensers andparticularly to improvements in condensers having sets of plates whichare adjusted relatively to each --other in order to'vary the'ca pacityof the con- 'denser.- r

-In radio receiving sets and other apparatus it has become common tomount a plurality of variable condensers so as to be simultaneously"act'ated rand adjusted by V the same means-fortuning and other purmounted ona common shaft or'other means may be provided for simultaneously adjust- Dueto' slight variations in the material employed, variations inthe space between the plates'and other incidents of manufacture,

thecap'acities of substantially'identical condensers vary slightly; alsothe character- 'istics'of the apparatus in the circuits with 'which theseveral condensersare employed may be such :that the circuit functionmost satisfactorilywhen the'capacity of the several condensers are slightly different.

"Theobje ct s of the present invention is,

' therefore, to provide means whereby the initial or basic capacities ofthe condensers may be adjusted or varied so that each of the condensersof the series or gang of condensers will have the correct capacity togive the most satisfactory results when the several condensers areoperated in unison. In the present embodiment .of the invention thisinitial adjustment of the capacity of an individual condenser isaccomplished by varying the from a detailed description thereof taken inconnection with the accompanying drawings in'which:

.Fig'. 1 shows an end view of one of the individual condensers of thepresent inven- Fig. 2-is a' plan view ofthe device of Fig. 1;

Fig. 3 is a view of the opposite end the device shown in Fig; 1';:; I

h condenser having at the opposite ends thereof the upwardly extending:sarmsll and 12,

provided atlthe nPpenen'ds'ithereof-Jwith the aligned openings 13 and15k through which'extends the shaft '15. :Theopenings 13 and 14 arecounter-sunk on their opposed faces to receive the cone-shaped -bearingmembers '17 and 18 which-arefi xed to thegshaft 15 by means of the setscrews-19.

Secured to the base 10 on-the opposite sides thereof by means ofuscrews2O are-the blocks 21 of insulating material.

Secured to each of theblocks 21 by means of rivets 22is a bracket23-having upwardly and outwardly extending arms 23 which are connectedby means'of' an integrally formed strip 24 which-is providcd withnotches 25. A plate member 24; provided with notches 25 and which restson the strip 24 of the bracket 23 cooperates with notches 25' in thestrip 24 to form slots 60 adapted to receive the lugs 26 extendingoutwardly from the opposite lower sides of each of the stationary plates27. The lugs 26 of the plates 27 may be secured within the notches 25 inany desired manner as by means of solder. -Associated with each ofthebrackets 23 is a terminal clip 27. Secured to the arm 12 by means of thescrew 28 is a bracket 29 provided at the upper end thereof with asplitbearing 30 controlled by the set screw 31 by means of which the drag onthe shaft may be regulated.

The movable plates 32 of the condenser are 'fixed to the shaft 15 andpass between the In the present embodiment of the invention each of theplates is provided substantially centrally of its fiat side with theupwardly extending portion 33 provided with an opening adapted toreceive the shaft 15.

As shown herein there are six movable plates 32 arranged respectively inthe spaces between the seven fixed plates 27. Surrounding the shaft onopposite sides of the set of six movable plates are the mounting blocksor plates 34and 35, (see Fig. 4). Fixed to the block 35 is a sleeve 36secured to the shaft 15 by means of the set screw 37: The plates ormounting blocks 34 and 35 are rigidly joined by means of the fiat platesor strips 38,

' provided with the slots 39 arranged to receive the edges 40 of notchesprovided in the upwardly extending portions 33 of the movable plates 32.The plates 32 may be rigidly secured to the strips 38 by solder or inany other desired manner. It will readily be seen that inthisstructure-the group of movable plates is mounte d as a rigid unit ontheshaft 15, butrinay be adjusted longitudinally on the shaft in orderproperly to space the movable plates between the fixed orstationaryplates.

:As above explained, where the condensers of a receivin or other circuitare arranged to beadjusted simultaneously by a common adjusting means,it isdesirable to provide means wherebyzthe initial capacity of theindividual condensers of the group maybe varied or adcondensers, such asabove described, are

shown mounted on a common shaft adapted 'to be rotated by the worm wheel44 driven by the worm 45 through the medium of the hand wheel 46. Theshaft I5 may be onecontinuous shaft but preferably three of theindividual condensers are mounted on a common base or support 47 withtheir shaft-s 15 in alignment, the adjacent ends'of the shafts beingjoined by suitable connecting devices 48. Thus when the hand wheel 46 isrotated the movable plates ofe-ach of the three condensers aresimultaneously operated in a like manner. In order that each of theseindividual condenseis may be adjusted so t'hatthe capacities thereof arein accordance with the properties of the section of the receivingcircuit with which it is employed the plates 41 may be adj ustedlongitudinally of the supporting shaft.

While in' the above disclosure but a single embodiment of the inventionhas been disclosed it is to be understood that many variations in thedetails of the invention are contemplated and the invention, therefore,should be limited merely by the scope of the appended claims.

Having described, my invention what I claim is new and-desire to secureby'Letters Patent of the United States is:

1. In a condenser, a plurality gf fixied plates, a 'pluralityj'ofmovablemlatess'upported on a rotatable shaftjmeans' for movin'g saidmovable plates simultaneously in relation to said fixed plates andindependent means slidable onisaid shaft for varying the relation ofcertain of said movable plates to said fixed plates, saidcertainTmovablei plates niountedon said rotatable shaft and adapted to berotatedtherebyr111- 1 -r 2. In. a-condenser, aaplurality ofhfixedplates, a plurality of movablei-platesi-asso-i. 35

ciated therewith supported on a rotatable shaft, means for aotatablynioving saidinflovable plates simultaneously :in relation! tozdaijdfixed plates and independent means slidable on said shaftffor-supporting-andrfor vary-= ing the space between certainlfixed-andmovable plates, said-certainiplatesmidtiptedz-tobe rotatedsimultaneously 1 witlirzthezether said movable plates. 1 rj ::o;:=.-:.-;:nm 3. In a condenser, -.a. a plates, a pluralityv oi-.movable..=platess associated therewith supported on a; rotatalile shaft,means forrot'atably movingsaidmovable plates simultaneously inrelatinnto sai fixed plates. j'means'adapteditQ surroundwa portionofi'said'shaft and to befldjustedim frictional relation. theretoand-bymeans of said frictional engagement. to II.1'a-intain the saidmovable plates in any-adjusted; position relative to said,fixedtp'lates; jand-emeanswioradjusting one 1 of said movable iplatesllaterally in relation to the-adjacent'plateswhereby the normal capacityof. the condenser may be varied, said laterally adjustable plate-,sup-

ported by said rotatable shaft and adapted.

to be rotated thereby.

4. In a condenser, a plura.lity,-o f-ffixed plates, a shafnaplurality-of movable plates carried by said shaft and adapted-to bepositioned between said fixed plates respectively,

an additional movable plate imounted, ona collar ad j ustably supportedon said shaft; and means permitting adjustment of said additional platesupported by said collar longlplurality of movable plates. 1 a

5. In a condenser, a plurality of fixed plates, :1 shaft,a'plurali't'yof movable "plates carried by said shaftand adapted tositioned between said fixed 'plates,' 'respectively, a collarlongitudinally adjustabieon tudinally of said shaft independentlyof.

said shaft and an additional' movable plate carried bysaid oollar.1 --r'i (S. In a condenser, a plurality of fixed plates, a shaft, a plurality:of movable plates- 1 carried by said shaft and adapted to pass betweensaid fixed plates, respectively, upon rotation of said shaft, meansadapted to surround a portion of said shaft and to be adjusted infrictional relation thereto and by means of said frictional engagementto maintain the said movable plates in any adjusted position relative tosaid fixed plates, and an additional movable plate carried by said shaftoutside of an outermost fixed plate, and means permitting adjustment ofsaid addi tional plate longitudinally of said shaft, independently ofsaid plurality of movable plates, wherebythe normal capacity of saidcondenser may be regulated, said additional plate adapted to be rotatedby said shaft simultaneously with the other of said movable plates.

7. In a condenser, a base, a plurality of fixed plates carried by saidbase, a shaft, a plurality of movable plates mounted as a unit on saidshaft and arranged to pass between said fixed plates, respectively, uponrotation of said shaft, means adapted to surround a portion of saidshaft and to be adjusted in frictional relation thereto and by means ofsaid frictional engagement to maintain the said movable plates in anyadjusted position relative to said fixed plates, an additional movableplate on said shaft outside of an outermost fixed plate and meanspermitting adjustment of said additional plate longitudinally of saidshaft, independently of said plurality of movable plates, whereby thenormal capacity of said condenser may be regulated, said additionalplate adapted to be rotated by said shaft simultaneously with the otherof said movable plates.

8. In a device of the character described, a plurality of condensers,each including a plurality of fixed plates and a plurality of movableplates arranged to pass between said fixed plates, respectively, asupport for said movable plates, a common actuating means for saidsupport, and an additional movable plate secured to means slidablycarried on said movable plate support associated with each plurality offixed plates and adjustable relatively thereto independently of thecorresponding plurality of movable plates, whereby the normal capacitiesof the condensers may be regulated.

9. In a device of the character described, a plurality of condensers,each including a plurality of fixed plates and a plurality of movableplates, a shaft upon which said movable plates are mounted, said movableplates being arranged to pass between the said fixed plates,respectively, upon rotation of said shaft, an additional movable platemounted on member slidable on said shaft at one side of an outermostfixed plate of each plurality of fixed plates and means permittingadjustment of said additional plates longitudinally of said shaft,independently of the corresponding plurality of movable plates, wherebythe normal capacities of said condensers may be regulated.

10. A device of the character described including a mounting frame, apair of insulating strips secured to said mounting frame, a plurality ofstationary plates, spacing members for supporting said stationary platesin spaced relation, means integral with certain of said spacing membersfor securing said stationary plates to said insulating strips, arotatable shaft supported by said mounting frame, a plurality of movableplates supported on said shaft and associated with said stationaryplates, means for rotatably moving said movable plates simultaneously inrelation to said stationary plates, and independent means slidable onsaid shaft for supporting and for varying the space between certainstationary and movable plates, said certain plates adapted to be rotatedsimultaneously with the other of said movable plates.

11. In a condenser, a U-shaped frame, stationary plates, spacing membersfor supporting and spacing said plates, means integrally formed withcertain of said spacing members attached to insulating strips secured tothe intermediate portion of said frame, a rotary shaft extending throughthe free ends of said frame, a plurality of movable plates carried bysaid shaft and adapted to be positioned between said stationary plates,respectively,

an additional movable plate mounted on a collar adjustably supported onsaid shaft and means permitting adjustment of said additional platesupported on said collar longitudinally of said shaft and independentlyof said plurality of movable plates.

In testimony whereof I have signed this specification.

HARRY H. IDE.

